イシイ　ヤスオ   Ishii Yasuo   石井　泰雄    所属   医学部 医学科    職種   講師
論文種別	原著
言語種別	英語
査読の有無	査読あり
表題	The surface ectoderm of the chick embryo exhibits dynamic variation in its response to neurogenic signals.
掲載誌名	正式名：The International journal of developmental biology 略　 称：Int J Dev Biol ISSNコード：(1696-3547)0214-6282(Linking)
掲載区分	国外
巻・号・頁	53(7),pp.1023-33
著者・共著者	Tripathi Vineeta-Bhasker, Ishii Yasuo, Abu-Elmagd Muhammad M, Scotting Paul J
担当区分	2nd著者
発行年月	2009
概要	The epibranchial placodes are specialized areas of surface ectoderm that make a vital contribution to the peripheral nervous system, producing sensory neurons of the cranial ganglia. They have long been characterized as a series of patches of thickened ectoderm in the vicinity of each pharyngeal cleft. We have previously demonstrated that Sox3 is not only expressed in these structures but also marks a larger, earlier domain. Here we demonstrate that neurons are produced from the Sox3-positive ectoderm that lies outside of the classically-defined epibranchial placodes. Our data show that these regions contribute neurons to the cranial ganglia, but then cease producing neurons as they lose Sox3 expression. We further demonstrate that the ectoderm in these regions is responsive to extracellular or intracellular stimuli that initiate aspects of neuronal differentiation. This response to neurogenic stimuli is lacking in regions of ectoderm distant from the normal sites of neurogenesis and the response to constitutively active Bmp receptor in particular, disappears coincident with loss of Sox3 expression. Finally, we show that a dominant repressor form of Sox3 blocks the ability of the ectoderm to undergo neurogenesis. Thus, Sox3 appears to be essential for the neurogenic capacity of surface ectoderm exhibited by the epibranchial placodes.
DOI	10.1387/ijdb.082780vt
PMID	19598119